Furnace-door.



L. S. SCHMIDT.

FURNACE DOOR.

APPLICATION men OCT. 5, 1915.

1,21 1,884. Patented Jan. 9, 1917.

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LAWRENCE S. SCHMIDT, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 SCHMIDT-MOCORMIGK COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OFPENNSYLVANIA.

FURNACE-DOOR.

Specification of Letters Patent.

Patented Jan. 9, 1917.

Application filed October 5, 1915. Serial No. 54,130.

To all whom it may concern:

Be it known that I, LAWRENCE S. SCHMIDT, a citizen of the United States,residing at Pittsburgh, in the county of Allegheny and tate ofPennsylvania, have invented certain new and useful Improvements inFurnace-Doors, of which the following is a specification.

My invention relates to improvements in furnace doors, and moreparticularly to water cooled furnace doors.

The invention is designed to provide a door comprising sheet metalplates suitably Welded together, and more particularly a door of thistype constructed in such manner as to reduce the liability to damage byheat and at the same time facilitate the construction of the door,together with a simplifying of the structure to provide for efficientwater circulation.

To these and other ends, the present invention consists in the improvedconstruction and combination of parts hereinafter fully described,illustrated in the accompanying drawings, and more particularly pointedout in the appended claims.

In the accompanying drawings, in which similar reference charactersindicate similar parts in each of the views, Figure 1 is a.

view in elevation showing a preferred form of door structure, the newshowing the mside face of the door with parts broken low sheet metalframe composed of an outer plate member 10 and an inner plate member 11.Each of these members is preferably formed from an integral sheet ofmetal, the two sheets of metal being practically integrally connected bywelding along lines presently referred to.

As shown in Figs. 5 and 6, the blanks for members 10 and 11 are eachrectangular in form, the excess of length over width being provided forthe formation of angularlyprojecting flanges, those of member 10, in-

tom of the door, the bending lines being 7 indicated at a in each case.The blank for member 11, however, is of larger area than member 10,owing to the fact that said member 11 is designed to provide a receivingspace or chamber for the refractory lining material 13, and in additionthereto, enters into the formation of the hollow top and bottomportions. This material receiving space or chamber is formed in member11 by depressing the central portion thereof;- this depression beingprovided in a con venient manner as by the operations of suitable diesand press, the bottom of the depression being preferably formedconcavoconvex or bilged, as at 11, the walls 11 of the depression beingpreferably of the character shown for the purpose of retaining therefractory lining in position, the portion of the blank surrounding thedepressed central portion forming faces 11". Members'lO and 11 are eachalso formed with an opening 14, preferably circular in contour, thewalls of these openings being flared, the direction of flare beingopposite in the two members, these flared portions not only serving asspacing elements when the members are assembled, but, in addition,forming Walls of an opening through which a tool, such as a bleeder bar,a stirring rod, or a test spoon may be entered through the door.

The members 10 and 11 are preferably jointed together by welding alongthe lines of the meeting edges of the two members. These edges are asfollows :At the top and bottom, the lines of weld are indicated at b inFig. 2, flanges 11 extending outwardly from a face 11 to meet the topand bottom edges of member 10; at the sides, the lines of welding areindicated at c in Fig. 3, flanges 10 extending inwardly and meeting theface portion 11 of member 11. This arrangement also places a line ofweld from the outer to the inner side of the door at each of its outercorners. In addition, the flared edges of openings 14 are weldedtogether as shown in Fig. 2. By this construction, the lines of weldwhich ex tend lengthwise of the door at the top and bottom are spaced amaximum distance away from the rear face of the door and from the heatof the furnace. This is a front face of the door.

. uniform.

great advantage in doors of this type and especially with respect to thelower portion of the door, as it is this portion which is subjected tothe intense heat as the door is moved over the furnace opening each timetheodoor is raised and lowered. It will be noted that my constructionpresents a non-welded water cooled' face to the furnace opening at thelower portion of the door.

The lines of Weld for the sides, which lines extend vertically, are notexposedto the direct action of the heat at any time, the sides of thedoor being protected from this heat by the door frame; hence, it is notnecessary to locate these lines of weld at or near the By thisconstruction, in addition to locatingthe lines of weld at points whereliability to damage from direct heat is practically eliminated, Idispense with a considerable amount of welding heretofore necessary indoors of this character and also place thelines of weld where theexpansion and contraction of the opposing metals are substantially Thisconstruction further provides the space 12 for the refractory lining,heretofore mentioned, and owing to the fact that the corners thereof arenot welded as heretofore, the bad effects due to the expansion andcontraction ofthe refractory mass at or on the corners is entirelyeliminated. I Another important and characteristic fea ture of thepresent invention is the fact that the lines of weld are located indifferent vertical planes'passing through the door,

thereby enabling the strength of the linesof weld to be reinforced bynon-welded portions and also preventing any damage that may possibly becaused to one line of weld being communicated to another line of weld.For instance, the line of weld indicated by b is in a different verticalplane than the line of weld 0 and an injury to line 6 would not becommunicated to line 0. The weld line b is strengthened by the bends bwhich are located substantially inthe vertical plane of weld linesb,"but which are located in an unwelded portion of member 10. Obviously,a similar effect is produced in connection with weld lines a by thebends 0' of member 11.

Water for cooling the door is introduced through a pipe 15 preferablyextending downwardly from the top of the door to a point adjacent thebottom,the open end of the pipe being located within a chamber formed bya member 16 angular in'cross section, and which has'one edge welded tothe bottom flange 11 as best shown in Fig. 2,

' said memberlfi preferably having its opposite edge in, contactwith theinner face of member 10, the intermediate portion preferably lying inclose contact with a wall of ber through the opening 16.

depression 11 Member 16 is preferably provided with a plurality ofopenings 16 both in its vertical and horizontal sides, these openingspermitting the water introduced through pipe 15 to pass into the portionof the door which forms the surrounding wall for the edges of therefractory material, and also into the space between the two members atthe back of the refractory material, the outlet being preferablyarranged at the upper portion of the door, as indicated for instance at17, in Fig. 1. This arrangement practically produces a settling chamber18 at the bottom of the door, the water entering this chamber from pipe15 and being required to pass out of this cham- 7 As a result, sedimentwould tend to collect in this chamber, especially in view of the factthat the flanges 10 and 11 are inclined outwardly toward the outer faceof the door, thus tending to form a pocket at the bottom of the doorwithin which this sediment could collect. For the purpose of readilyclearing this. chamber of sediment, I may provide suitable openings 19,normally closed in suitable manner, by means of which a tool may beintroduced into the chamber for cleaning out the sediment.

1 preferably protect the line of weld which joins the opposing edges ofopenings lt by a structure indicated at '20, and shown on an enlargedscale in Fig. 4, this structure comprising a pair of members 20 and 20"adapted to be connected together by one or more connecting devices, suchas screws or bolts 21, these members combinedly inclosing the line ofweld and the major portion of the flared parts surrounding this opening.The members 20 and 20 are annular in form, and hence not only act toprotect the line of weld, but also to reinforce the openings and flaredportions, tending to prevent damage to the members at this point. Aswill be obvious, these members 20 and 20 may be sufliciently large as towithstand wear under the movements of the bleeder bar or other tool fora great length of time, there being no relative movement between thesheet metal members and the members 20 and 20 and consequently littleliability of damaging the sheet metal members. While I prefer to providethis opening circular in contour, it will be obvious that this contourmay be varied as desired, the essential being that the structure 20shall completely inclose the outer face of the line of weld whichconnects the members 10 and 11 at this point as well as the flaredportions.

lVhile I have herein shown and described a preferred construction, itwill be readily understood that changes and modifications therein may berequired or desired to meet the various conditions of service, and I,therefore, desire to be understood as reserving the right to make anyand all such changes as may be found desirable or necessary, in so faras the same may fall within the spirit and scope of the invention asexpressed in the accompanying claims.

lVhat I claim is 1. A furnace door comprising a hollow sheet metalstructure formed of outer and inner sheets united together at theiredges to form a body chamber and communicating hollow side, top andbottom portions, the outer plate having side bends only, said innerplate having top and bottom bends entering into the hollow top andbottom portions, the uniting line of the bottom portion disposed on thelower outside edge of the door.

2. A furnace door comprising a hollow sheet metal structure formed ofouter and inner sheets united together at their edges to form a bodychamber and communicating hollow side, top and bottom portions, theouter plate having side bends only, said inner plate having top andbottom bends entering into the hollow top and bottom portions, saidmembers being united by welding, with the welding lines limited toopposed edges of diflerent plates.

A furnace door comprising a hollow sheet metal structure formed of outerand inner sheets united together at their edges to form a body chamberand communicating hollow side, top and bottom portions, the outer platehaving side bends only, said inner plate having top and bottom bendsentering into the hollow top and bottom portions, the uniting line ofthe bottom por tion being on a different vertical plane from that of theside portions.

4i. A furnace door comprising a hollow sheet metal structure formed ofsheets or plates shaped and united together at their edges to form abody chamber and com municating hollow side, top and bottom portions,the uniting line of the bottom portion being on a different verticalplane from that of the side portions and disposed at the lower outsideedge of the door.

5. A furnace door comprising a hollow sheet metal structure formed ofsheets or plates shaped and united together at their edges to form abody chamber and communicating hollow side, top and bottom portions, oneof said plates bent to form a flange constituting the outer peripheralwall of the bottom portion and the other bent to form a flangeconstituting the outer peripheral wall of a side portion when the platesare assembled.

6. A furnace door comprising a hollow sheet metal structure formed ofouter and inner sheets united together at their edges to form a bodychamber and communicating hollow side, top and bottom portions, theouter plate having side bends only, said inner plate having top andbottom bendsentering into the hollow top and bottom portions, and adepression to receive refractory material, said depression having itsbottom bilged.

7. A furnace door comprising a hollow structure formed of shaped platesor sheets of metal united together at their edges to form a body chamberand hollow side, top and bottom portions communicating with saidchamber, a settling chamber located at the bottom of and within thestructure and having open communication with the said body chamber andthe hollow portions, the peripheral wall of said structure havingopenings leading to said settling chamber to permit removal of sediment,and means for delivering a cooling agent to the settling chamber.

8. A furnace door comprising a hollow structure formed of shaped platemembers united to form a liquid-receiving structure, said members havingopenings, the walls of said openings being flared in opposite directionsto provide meeting edges adapted to be united by welding when themembers are assembled, and a reinforcing structure for protecting saiduniting line, said reinforcing structure comprising a pair of elementson opposite sides of said uniting line, each element extendingthroughout the length of said line and having a face adapted to fit theflared portion of one plate, and means for securing said elements inposition.

9. A furnace door comprising a hollow structure formed of shaped platemembers united to form a liquid-receiving structure,

, said members having openings, the walls of said openings being flaredin opposite directions to provide meeting edges adapted to be united bywelding when the members are assembled, and a reinforcing structure forprotecting said uniting line and the walls, said reinforcing structurecomprising a pair of complemental ring-like members having faces adaptedto abut each other on a line approximating the uniting line of saidplate members, each member having a face shaped to fit the flare of oneplate, and means for securing said complemental members together toprovide a structure extending laterally in both directions beyond theuniting line of the plate member.

In testimony whereof I affix my signature in presence of two witnesses.

LAWRENCE S. SCHMIDT. WVitnesses:

ALEX. S. MABoN, W. G. DOOLITTLE.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D G.

